Figure 6.

Assembly improvement with increasing coverage and read length. Simulated assembly results on all complete NCBI references as of January 2013 using
PacBio RS C1, C2, XL-C2, XL-XL, and projected 'ZL’ chemistries. The two figures show
the percentage of genomes closed (left) and the average number of remaining gaps (right)
with increasing sequencing coverage. C2 and newer chemistries can span the rDNA repeat
and thus close many more genomes than the C1 chemistry. However, beyond 150× C2 there
is limited benefit from further sequencing because the remaining repeats are too long
to resolve. The longer chemistries saturate most repeats and gain little benefit from
additional coverage over 50×. Resolving the remaining repeats requires a jump in sequence
length to hundreds of kilobases.